SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a867f24fef155e4a652ea615eb9f5d03710282e7155c9f56315b223991278f39' 
  AND token = 'P+3+u4Y5mAFpIGgs2bf+lpALFQNQAxRhI51M9vbZQI8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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