SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f414074cceaa5fb96d6084bbacd13865751427715850ffef54866bc33f1d00e5' 
  AND token = 'iYGlEAYcCFUu9vwo90/C/VfwCqRoHRvpnu5e/KXL7kQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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