SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccae4e3ba48f29a3705e19298b2a64e558a7821987b6267a646ca6d2d08fe598' 
  AND token = 'q1ercX+m6mmTnyLJIAU8vh5K20xq/x3UXaTIsyAaqNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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