SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c6e6cd71f9aba396d962203ddd5f7a3d3ac7a01ab95814e738dbf5ed83edd320' 
  AND token = 'oZANmOPw22tous5DO1MoV/+50KqDqyd+VT2bm6xmfO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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