SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0a0d4bb02cf2332773e15a291f20df9d1879c86004e693afd7f17255711fea48' 
  AND token = 'eMicMarwqBU3ZCIbADn61XLDVLn/RNW0GVvx8iLBvHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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