SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61ddd74f822d91bcff6c6cbbdc42a28b3b504d32cf6a07f155d49a8c2f4436f3' 
  AND token = 'lY97HKTTo0giBjsoRG3+t8S1iPYrQqbLT6KsqZMBOwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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