SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bef5ce381b5e7982e14569d65faaa6148d57a82b2795240afb697b38b67a4975' 
  AND token = '1vzzeKEtJGtTJdM/kWv6OMGHVYCiInq9g4eY2OfvfdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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