SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11773667c926ad0d97167126a67de76664f2c1a0a8d4dd3b9590802a51843ffa' 
  AND token = 'PGx/HWhZSWDYbJVEX0OIJ74OmgTvrtTSbL9EeRgCyCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}