SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec92fb76c460fd10e7f2bff7b0fb8f25498b16d37158995f48d0c01622d3e9c5' 
  AND token = '8po6aCiID5CBCcLoQH10Kp1VKipfpGdjLwSY2n816Y0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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