SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e74eeb514afd90b654fe828301f1655c2244274b557ea50e34537d1b2e8396e7' 
  AND token = 'h2DVrm2hhzQVYEnbnI9CWY1Fyl9FuA+FMrWDELiDYWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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