SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65264f519ab351889f7a3009e41103af6fb1294c6f9dadd3d585522a24ddac64' 
  AND token = 'ih+r9qGGevmF4TxevY7V6L3ZjWnaS/2CYy8i5Lj7s5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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