SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5dd1a9ea15f8663323cfe568487863b3e205b087772af53e9622a63983bdcdd2' 
  AND token = 'OM1Dxeyt4g5Yh+Lt9ARnzkUFTROqylWP5IwVHuCJD50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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