SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6eeb450fcbc8e57db2a52875ff054c2385b2efe67367ffd3f468c9cdd5060e80' 
  AND token = '1qq7DPD4yrax2rPkBc8pf8+QUtsfiUuAyzn9o5bOoRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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