SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b87cdbc85376049bb0ddd2139fdd17ab213acb21637aace84105557e1e35ef5' 
  AND token = 'pBIowixuqOf82SZQHA/J2GEKpDqxn1q+ungMiTQwnNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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