SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e2529d4730a4230d57cfb51e1c3c92de426c9f55693f5017ae6b2dfbb98ae0b' 
  AND token = '1GuXveGlb1/RBVzHF1UBRFqw2YDvAhILnOncR/zOYBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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