SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd52ce29e879fdc9348862dbf2cd001a240d5ee4c18f5be5bc56bf9e5b3a73266' 
  AND token = 'D7kzbTq4YIhqVrjWCxHCLGDvo80oBw0j9XcUMxmMLfE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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