SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4300001f0904c8fabedd5efd8432d0666c912a74032dba8e71aed0bf4a18fa9f' 
  AND token = 'T2OM/sOwjZilsdjK5cRWHJv73SoeRuD6UP5omYncX0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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