SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd31f791fcb92afc4af605328d621f398fba2cad2f6c65da909dcb8ac67266252' 
  AND token = 'BoHZvxt7pC6BQK5RVwzu09H9a/KNvEKxXwekR6eROvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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