SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '63350cc2f4df95e243166eda94d30ab2b75fc2615958c5226541676f11afcba4' 
  AND token = 'WHdW9LjNUwZ3y3rkTLguyZFDFeWY5YUVYmiCM1mM06c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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