SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5725d42f632c319abf552b47479e557f983db9d9513a13e101ea75147bce1bb' 
  AND token = 'dGT2O0WTvlBk/cY3bhFtw+QyYzzZxL2hAG91Ew9FWLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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