SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c703778d490d3dba355ba3d68eae63b707e33637329f8617a881d00405fffd2' 
  AND token = 'g1yWF2WWwAY1fR5gz4pkEsDtnhueZ8paMONQRKAANS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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