SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2683a6e2d6d104160020ecc36d5534aa30433268eb02a7ac40f04e9148098321' 
  AND token = 'O0g8E7YyHUpIunRpK/TByr23Y+OASrk2IB8En1q0Qsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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