SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '970004079e70b5b26a997979386fc93ec0f101bdfbdd5288eb19432a44ea1f13' 
  AND token = '+wa9NUCrnny4TptuHSQYyRrysKE78jCGIgABNPFKbbg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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