SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e9c00ed0e912ffb526192053609375a25bc3a77adaed1dedba85dd518e144472' 
  AND token = 'B8vromPGfQxh/IhkNy/nM2Sweu8BVoMJeijbYcthaEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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