SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b116e7d43e6b24900bffbcc6fa96bc4168aa836445ede7f8cf2e405c5ad84402' 
  AND token = 'E7cdVNCXwyv8Tnm7nsYCVngwMFyokmSbzXW0DycFBNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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