SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e3e18fe1fdd5b9406e863a2714867ffc31618d37ad1596845664ff14498072d' 
  AND token = 'W/Ge8MILuw2JDqCpUu0pU5BVld9e0jqgiBxkzOBD13E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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