SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '853515fdade3494128c58e79290388b6470599ff080d60c40679da76e8bb20e7' 
  AND token = 'fVeUTcMOlJAPr4BBPxu0OzxYw15Cnn518/aP1B3qAzo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}