SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81c3a238b0a5e72593bbdb53f105326ba3160623375264acea3a8da6874b6ded' 
  AND token = 'Tl/HShIR/ss9qly6yyoCSuIzaspKQYkOHpeOZOPFOZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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