SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f00cdcb6349e67a654e7be05ddb861f3dd06aeb09d6522f9cb290f140ef5128' 
  AND token = 'nidlMCVAqW3Q472K41Bvg1cYCwX71QXQgm22bUBquN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}