SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7070f42409612cde8320990f2a1b9619b3bd09402332f824e283e41d5579e37a' 
  AND token = 'Dw0inOp/gUnZ7MsYnzWh0rjQds2GKO5C4Q+XEBpDO2I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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