SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be35fa2e11788923752824f2bc38af484ffa496b479a1ddcce0a31ac47091c2f' 
  AND token = 'tT+Q4Ut4R7FdkHMxzHh74n7wif33oLRwGnmTNrvFDy4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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