SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e68cc09906b1be335b3d342cc0cc71a69f0a916d503f0a74182cdb05552a320' 
  AND token = 'E2Wrn87/BPsgOv3Lo06MTb2BepBvNUOUjG2AMCXo9Ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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