SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c5f19f03323abfbc0caa70db92d2f2b15f0ce2165eba897190bebee9506a641e' 
  AND token = 'ENSSeAu4PuDtw2TgjaDEsk195R1ptuvaIcXZ660PHnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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