SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11c07f0235344dab81f5dfd482608b19b6a62d51fcc6e726779039eea8536ed7' 
  AND token = 'VIpJuVJPPPE1NfLUEvMTCgDEE0htbFa+4V2aG7FpJO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}