SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '707a63386f00b6d30ee1b61357ee6ea79413015c33355db2f293bc8b2993d2d0' 
  AND token = 'V3u/amGMADuLfacu+hcZnb0ephZ9OJbu97Ssdb3XRqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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