SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3b69a9f3e4940bfbe4f3a9cce950bc943dca0e02161a1badf903972058a5757' 
  AND token = 'CnFp6QpHOtbsCoIRN8gSngws45u/QsF00L5Ar7zD3+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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