SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbb53cf0b1bf11ffaac22c09e7ca58fdee1ceb5ef511a70748fb9e93225b9d8a' 
  AND token = 'P7PMyA9roHLWP3bJKHF+TLot68184GWllQldy21h71I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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