SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f4708854de88eecbb2b201f4336cc6f40efe1c4fc99cf46a5a7660640627e09d' 
  AND token = 'jPZN1c9dSBelbdRtsP4tOTtSbYctTEW4rPMqbLjm938=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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