SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afbd010c1d18cd00c20ca247ec0269ef18064627b92dbfadb8490e888553a3e0' 
  AND token = 'Omw4M90DIs4tvStzj3YEnmksTC0NB1R+ZTaGUABjMGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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