SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2caaaf6457f96019f1564c4747bf1213e420b2ebdf2e976e770e7bdd277eb6c' 
  AND token = 'LOaRMUpWFyrfPnG4/73RaaKcp8o1095NdlzLzxuAk8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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