SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '876415953b9d5b68cd6a596239fc560e6850bae310cce6178e42f1ff8b79e191' 
  AND token = 'jd4HDzUx80rUqnjeaXAYA5lKafhYQN4Y517D28xEc7Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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