SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '14e2630ee1756b7c4329416db050b8da9b015a25f0decba3c9d1c037b48c7d3e' 
  AND token = 'pv6xw0csmPyzIC5gChp5AerJEvtES/4XOOniiHr7rEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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